Party Wall
by TheBadIdeaBears
Summary: Izuku moves to a new building and half of his stuff is missing. Thankfully he has a hot new neighbour he can ask for help.


**For new year, Holly asked me for a fic where Izuku and Bakugou share a party wall and things get hot and heavy between them - I hope you enjoy this as much as she did. :) ~ Pan**

* * *

When Katsuki returns from the gym, he finds a removals van parked outside with people carrying furniture and boxes into the building. Figuring someone must be moving in, he leaves the security door on the latch (normally he would make a point of letting it shut properly like it's supposed to) and heads upstairs. There he sees the door to the flat next to his own propped open with a large box labelled 'KITCHEN' and breathes a sigh of relief: whoever is moving in has to be better than his previous neighbour. Even if they have violently pink hair they might not play obnoxious dance music at all hours like Mina did. Determined not to be in anyone's way, he ignores his curiosity and goes into his own flat.

After a shower he sits down at his desk with a coffee to look through his emails when he hears a knock at the door. Opening it, he comes face to face with a guy, probably a similar age to himself but a little shorter, with dark green hair and freckles. The guy gives him a smile and Katsuki feels his heart give an irresistible throb.

"Hey," says the guy. "I'm really sorry to bother you but I just moved in next door and half my stuff hasn't arrived yet – I was wondering if I could borrow a screwdriver please?"

Katsuki nods. "Sure thing, let me have a look."

He leaves the guy in the doorway and opens his store cupboard to seek out his toolbox.

"Have you lived here long?" the guy asks.

"A couple of years," says Katsuki, shoving his Christmas tree out of the way.

"Anything I should know about?"

Katsuki straightens, toolbox in his hands as he returns to the front door. "Don't use the dryer nearest the window in the laundry room – it doesn't really dry anything properly and it smells funny," he instructs. "Bin day is Friday so the store smells less bad if you go after they collect it that day. Other than that it's pretty standard stuff like don't be obnoxious and don't let your post overflow."

"Cool," says the green haired guy. "Thank you."

"I figured if you didn't have a screwdriver you didn't have any other tools either," adds Katsuki, holding out the toolbox. "Just bring it back whenever you're done with it."

"Thank you so much – again." The guy takes it with a grateful nod. "I'll bring them back as soon as I can."

"No rush," says Katsuki. "It's not like I frequently do DIY."

"Okay then – I'll stop bothering you."

Katsuki laughs. "It's fine – I don't mind. Let me know if you need anything else."

"Okay, I might see you later then." The guy turns to go, getting a few paces away before turning back. "I'm Izuku by the way."

"I'm Katsuki," says Katsuki.

Izuku grins: it seems to light up the whole hallway. "Nice to meet you Katsuki."

* * *

Izuku sags against his kitchen counter, watching the little saucepan of water on the stove slowly heat up. Despite having moved in four days ago, and having called the removals company at least three times a day in that time, the other half of his stuff still has not turned up yet. That includes his kettle and sofa, among other things, but thankfully he has his bed so he has avoided sleeping in a ball on the floor at least.

His job mercifully starts in a few weeks so he has time to get himself sorted in the meantime and he has been keeping himself busy going to the climbing centre and the library in between calling and emailing the removals company. If nothing else, his shoulders are getting a good workout.

The neighbours seem pretty nice too. On one side of him lives a young woman called Toru – apparently that is; he hasn't seen her yet and from what people here have told him he's unlikely to see much of her. Across the hall lives a little old woman named Mrs Shuzenji who seems to like wearing a syringe in her hair. And then there's Katsuki on the other side... Izuku bites his lip on a grin thinking about him – there was no way to miss those strong shoulders in the tank top he was wearing, nor the effortlessly sexy way he moved and talked.

The toolbox Katsuki lent him sits on the corner of the kitchen island, seeming to stare at him. Katsuki seemed happy enough for him to borrow it for as long as he needed, but Izuku doesn't want to take the piss; given that he's unlikely to get any more bits of furniture to put together any time soon, he can stand to return it to him whenever. If he does, he'll get to see him again, and maybe that's why he's dragging his heels a little: the idea of seeing Katsuki again is exciting but so is the anticipation of seeing him again.

The saucepan bubbles and Izuku takes it off the stove, pouring the contents over a teabag in his favourite All Might mug before taking the pan over to the sink. In the window, and the dark late evening beyond, Izuku sees his own reflection gazing back at him as he rinses the pan and puts it on the draining board. He'll give the toolbox back in the morning, he decides, returning to his tea and sitting on the floor to watch TV while he drinks.

When he climbs into bed later, he stretches under his duvet, making a mental to do list for the morning. He needs to call the removals company again (obviously) and he'd like to try the orange track on that wall he climbed the other day, plus he knows he wants to give Katsuki back his toolbox. Maybe he could invite him to come climbing?

Izuku's thoughts are interrupted by the sound of a soft moan. He pauses, lifting his head. The walls here aren't particularly thick – he's heard radios and the general sounds of people pottering around over the last few days – so it's not unusual to hear something from next door, but this particular sound...

He hears it again and feels a flush come into his cheeks. Having looked at the windows on the outside of the building, he knows his flat and the one next door are mirror images of one another architecturally, and given the side he heard the sound from, he knows it came from Katsuki's bedroom.

Another muffled groan comes from the other side of the party wall and goes right through Izuku, settling low in his stomach. Knowing that Katsuki, separated from him by only a stud wall, is having sex – or more likely touching himself seeing as Izuku can't hear any other voices – feels oddly intimate, and it's making Izuku's pulse quicken. When he hears more noises of pleasure from Katsuki he tries to resist the urge to touch himself for only a little longer before sighing and sliding his hand into his pyjama bottoms, grasping his erection. He starts to stroke his cock, slowly at first but soon speeding up as he imagines the wall gone and Katsuki's body beside his own. How would Katsuki touch him, he wonders, or would he want to watch Izuku touching himself? Both ideas have Izuku biting back his own moans as he keeps pumping his hand, listening to Katsuki next door. He wants to know how Katsuki's body feels, chest pressed against him, arms around him, hands touching him all over.

Katsuki's moans grow louder and Izuku gasps, feeling his orgasm fast approaching. It takes only a few more strokes of his hand and the thought of Katsuki's lips exploring his skin before he comes, his body shaking as he cries out. Next door, Katsuki's climactic groan seems to falter ever so slightly, and Izuku has to wonder if he heard him. As he catches his breath, he pulls back his duvet so he can go clean up and feels his cheeks blazing.

* * *

Katsuki rinses toothpaste from his mouth before straightening and looking at himself in the wide bathroom mirror. His hair sticks up further on one side than the other and he runs his fingers through it to try and make it look a little less chaotic. He's debating getting out his hair gel when he hears a knock at the door. Answering it, he finds Izuku standing there, carrying Katsuki's toolbox and seemingly dressed for the gym. As their eyes meet, Izuku flushes and Katsuki knows they're both thinking about last night.

He's grown used to being able to be loud while masturbating as Mina's constant music playing drowned him out, but without that (he now realises) others may be able to hear him... especially if their bedrooms share a party wall. Not that he's embarrassed exactly: by the sounds of it, Izuku was rather enjoying himself too.

"Hey," Katsuki says, leaning on his door frame with a smile. "How are you?"

"I'm good," says Izuku, giving him a little smile back. Under his freckles he's still blushing and Katsuki wants nothing more than to kiss those warm cheeks. "I just thought I should bring you your tools back."

He holds out the box and Katsuki takes it, putting it on the floor at his feet. "You didn't need to bring it back so soon you know."

"I know," says Izuku. "But I wanted to..."

He meets his gaze and Katsuki grins. "Couldn't stay away?"

"Uh..." Izuku's ears go pink and Katsuki can't keep from laughing.

"Don't worry," he says. "I'm really glad you came by."

Izuku beams up at him. "Well I won't keep you long – I was on my way out."

"Where are you off to?" asks Katsuki, eyeing Izuku's rucksack and exercise gear. "Gym?"

Izuku shakes his head. "Climbing centre."

"Ah so that's where those arms come from," comments Katsuki with an appreciative look up and down Izuku's body. "I wondered."

Izuku gives him a pleased look. "Do you climb?"

"I've done it," says Katsuki. "Not for a while but I'm sure I could pick it up."

"Well you'd be welcome to join me sometime," says Izuku. "I could show you some stuff."

"I bet you could," grins Katsuki.

Izuku's face turns pink again but he nods. "I'll see you later then."

He turns to go, walking off down the hallway, and Katsuki watches him go – or rather, watches his ass.

"See you later," he says with one last grin.

* * *

The next night, Katsuki is reading in bed when he thinks he hears a sigh from the other side – Izuku's side – of the wall. He pauses, lifting his head and tilting it to one side as he listens intently for any more sounds. Part of him wonders if he's kind of a pervert for actively listening out for it but on the other hand Izuku knows how thin the walls here are and could certainly try harder to keep quiet. When he hears a quiet whine his suspicions are confirmed and he puts down his book, feeling his body stirring in interest already as he pushes aside his duvet. As he wraps his hand around his half hard cock, he lets out a groan of his own that he knows will have been heard through the wall. He strokes his hand up and down, feeling himself hardening further against his palm and letting out a shuddery breath.

Between the sounds of pleasure next door and his own hand and wild thoughts, Katsuki starts moaning in earnest. He's never done anything as weird as this before, but he can hardly bring himself to care right now, while he imagines Izuku's face, blushing in arousal as he jerks himself off only feet away to the sound of Katsuki's voice. A strangled moan comes through the wall and Katsuki wishes it were in his ear, wishes he could hold Izuku close and feel his body against his own. He wants to touch him, fuck him, feel him come apart underneath him.

When Izuku lets out a loud cry, Katsuki lets go, coming hard with a growl of Izuku's name. As he comes down from the high he hears a breathless laugh from next door and resolves to ask Izuku out next time he sees him.

* * *

It takes a while before their paths cross again. Though he tries to avoid it – working from home is vastly preferable – Katsuki gets summoned to the office every day the following week. The most he sees of Izuku is at a distance: he sees him once when he's on his way home from the office with a tall guy with glasses and another time at the supermarket. Katsuki goes to say hello to him but then sees Izuku's headphones in and decides to leave him in peace – he wouldn't want to be interrupted in Izuku's position after all.

The next time Katsuki sees Izuku things don't go to plan. It's early Saturday morning and Katsuki is locking his front door to go to the gym when he hears Izuku's door open. Hoping that he might be able to catch Izuku before he goes wherever he's going, Katsuki lingers by his own door, unnecessarily checking his pockets for his phone, wallet and keys as he waits for Izuku to emerge. However, instead of Izuku's familiar green mop of hair, Katsuki sees a guy come out whose hair is half white and half red. He's smiling at Izuku and Katsuki feels a drop in his stomach as he watches Izuku pull the guy in for a hug.

"Thanks for coming to see me," says Izuku, obvious fondness in his voice as he pulls back again. Katsuki sees a smile on his face when he looks at him.

"I missed you," says the red and white haired guy.

"I missed you too," says Izuku. "Don't be a stranger."

"See you soon?"

"I really hope so."

The pair say their goodbyes and the unfamiliar man leaves, walking away down the corridor. Izuku closes his door and Katsuki feels his brows pull down in a frown before he turns to leave for the gym. Did he get his hopes up for nothing?

* * *

With a heavy sigh, Izuku hangs up the phone. Even after nearly two weeks, the other half of his stuff still hasn't appeared and his patience is waning rapidly. He's planning to leave a scathing Yelp review once all this is over; he can't think what to do about the problem but all the other reviews for the company were extremely positive and he can't let that stand.

Getting a visit from Shouto helped give him something fun to think about for a couple of days, even if they had to sit on the floor the whole time he was here. Not only that, but Shouto served as a good sounding board for Izuku with regard to Katsuki: Izuku feels surer about the idea of asking Katsuki out... if he ever manages to get hold of him again. Whenever he's seen Katsuki over the last few days, he hasn't been able to speak to him. Either he hasn't been able to catch up to him or when he does Katsuki seems closed off, his previous enthusiasm apparently dimmed. Izuku doesn't understand it; weren't they getting along before? What changed?

Nevertheless, he's determined to ask him out, even if he gets shot down.

* * *

Katsuki lets out a huff as he turns off his bedside light to go to sleep. It was a long, stressful day at work and he's now exhausted and keen to just rest.

Unfortunately Izuku has other ideas: Katsuki hears a telltale groan through the wall and suppresses a grumble of annoyance. Sure, he'd be glad to get a visit from his boyfriend or whatever too (if he had one), but does Izuku have to be so obnoxious about it? The sting of being led on as he has been makes Katsuki roll onto his other side to try and ignore the noises Izuku is making, even as his body tries to show interest. He assumes Izuku is with his boyfriend at least, unless he's trying to get Katsuki involved in some 'not quite cheating but still kind of cheating' thing. Either way, he wants no part of it and silently wishes for it to be over quickly.

Izuku's moans of pleasure continue, increasing in volume and pitch; Katsuki almost pulls his pillow around his ears to try and muffle them but just before he reaches to do so, he hears something that makes his heart stop: Izuku gasping his name. Sitting up, Katsuki listens to the sounds more, trying to listen out for any more distinct words therein. Soon, he hears it again, and he's sure he heard correctly this time. Katsuki shakes his head to himself as he hears Izuku coming next door.

 _What the actual fuck?_

* * *

With this head halfway inside the tumble dryer to look for a missing sock, Izuku barely hears someone else walk into the laundry room. When he pulls his head out, however, he turns to see Katsuki at another one of the dryers, looking sullen as he sees a few minutes left on it.

"Katsuki?" he asks. Katsuki looks at him and Izuku is surprised at the expression on his face: there's confusion in his eyes and Izuku isn't sure why. When Katsuki says nothing to him, Izuku asks, "Uh... are you okay?"

"Fine," says Katsuki, dropping his gaze to the dryer's display once more.

Izuku pauses again, sock in hand, gazing at him. After a few more awkward moments of silence, Izuku says, "I haven't seen you in a while."

"Been busy."

"Right..."

Izuku frowns to himself. How is he meant to ask Katsuki out if he's acting like this? He drops his sock in his laundry basket, taking time to check through the rest of his socks to pair them up and make sure he hasn't lost any while Katsuki's dryer rumbles on. Just as he's trying to decide if he should just ask it fast and get it over with, however, Katsuki finally speaks again.

"So how did your boyfriend feel about you saying someone else's name last night?"

Izuku feels his eyes go wide as he looks at Katsuki. "Boyfriend?"

"The red and white hair guy who looks like a walking candy cane," says Katsuki. "You been together long?"

Blinking in surprise, Izuku can't suppress a laugh. "You mean Shouto?"

Katsuki shrugs. "I don't know his name, just saw him leaving yours one morning."

"Shouto isn't my boyfriend," says Izuku with another laugh.

The dryer _pings_ to say the cycle is finished but Katsuki continues looking at Izuku. "He's not?"

Izuku shakes his head. "No – just a really good friend." The last week flashes by in Izuku's mind and his eyebrows rise in realisation. "Is that why you've been kind of weird this week?"

"Oh..." Katsuki gives him a sheepish look. "Yeah, I... didn't want to intrude on anything or be the 'other man', you know?"

"Yeah, it's understandable," says Izuku. He hesitates only for a moment before starting, "Hey, Katsu–" His phone starts ringing in his pocket and he pulls it out, seeing the removals company name on the screen. "Uh... sorry, I really need to answer this..."

"Go ahead," says Katsuki with a nod.

As Izuku takes the phone call, Katsuki opens the dryer and starts taking his stuff out of it, his expression brightened massively compared to when he first walked into the room. Soon, Izuku hangs up with a grin.

"Good news?" asks Katsuki.

"They found the rest of my stuff," says Izuku.

"Wow, took them long enough," says Katsuki. "Where was it?"

"In a van parked at one of their depots apparently," says Izuku. "They're bringing it by tomorrow."

"That's great," says Katsuki. He leans against the dryer, still gazing at Izuku. "So... if that guy isn't your boyfriend and you don't have one... would you maybe want to join me for dinner next week?"

Izuku beams. "That sounds amazing."

* * *

They barely part their lips as Katsuki unlocks and opens his front door, both of them practically falling into the flat and closing the door behind them. The wine they had at dinner makes Katsuki feel surer of himself as he keeps holding Izuku close, feeling Izuku's pulse racing through his body. Both toe their shoes off, shrugging off their jackets and leaving them where they fall on the floor in the interest of continuing to kiss one another. When they do finally stop to take a breath, Izuku looks up at him with a flush in his cheeks and widely blown pupils.

"You okay?" asks Katsuki, cupping Izuku's face in his hands.

Izuku nods, giving him a smile. "I'm great," he says. "Thanks for dinner."

"You're welcome," grins Katsuki, leaning in to steal another quick kiss from Izuku. "Seems we've ended up back at mine."

"Seems so," says Izuku with a coy quirk of his eyebrow. "You going to show me a good time?"

"Fucking right I am," says Katsuki, lifting Izuku in his arms and starting to kiss him once again. Izuku wraps his legs around Katsuki's waist, letting himself be carried through to Katsuki's bedroom, where they collapse together on the bed, tugging at each other's clothes.

All of Katsuki's fantasies about Izuku seem to be coming true, especially when they part again and Izuku immediately starts nibbling at Katsuki's neck, pulling his collar aside to get access to his skin. He grinds down in Katsuki's lap, drawing a moan from him and making him grab at Izuku's backside through his trousers.

"Fuck, you're incredible," Katsuki breathes, moving his hands round to Izuku's front to start removing his clothes. Their shirts are soon discarded on the floor and Katsuki feels Izuku's nails rake down his sides as he flicks his tongue over one of Izuku's nipples.

"Ah, Katsuki!"

"You sound so much better in person," says Katsuki with a grin.

"So do you." Izuku lowers his hands, undoing his trousers and Katsuki's so they can both get out of them. As Katsuki returns his attention to Izuku, climbing back into his lap, he sees a flash of something in Izuku's eyes. "Do you have condoms?"

Katsuki's answering grin is wide and wicked. "I do – you sure?"

"Completely," says Izuku.

Katsuki retrieves a condom and lube, pulling Izuku back into another kiss as he pops open the bottle and starts slicking up his fingers. When he eases the first inside Izuku, the answering gasping moan breaks their kiss and seems to get him even harder – somehow.

"You sound fucking beautiful," says Katsuki, continuing to finger Izuku open. Izuku whimpers, starting to slowly roll his hips back into Katsuki's touch, urging him to touch him more. As he moves more fingers in and out of Izuku, Katsuki gets more moans and sighs of his own name, the sound sending another thrill through him.

"Ka... Katsuki..." Izuku breathes, shuddering against him as Katsuki nudges his prostate.

"Yeah?" Katsuki moves his fingers a little more, grinning again when Izuku moans once again. "You okay gorgeous?"

Izuku nods, a blush high in his freckled cheeks. "Please... fuck me."

"Gladly."

Katsuki withdraws his fingers carefully, reaching for the condom and putting it on, dousing his cock in more lube. With only a little assistance, Izuku moves in his lap, sinking down onto Katsuki's cock with a whine. After pausing for a brief time to give Izuku time to adjust, Katsuki pulls him close with strong arms and stands, lifting Izuku over to the wall where he pins him.

"This okay?" he asks, getting a nod in response.

"Yeah, feels good," Izuku gasps. "Please... you can move."

Needing no further encouragement, Katsuki starts slowly thrusting, moving his hips back and forth. Izuku gasps again, clinging to him, digging his nails into Katsuki's shoulders. Katsuki's movements grow faster, more urgent, rocking into Izuku with the wall to support him. A grin comes to Katsuki's face as he thinks of the times when they were separated by only this wall. Every part of Katsuki burns with desire, wants to make Izuku feels as good as he feels – from the noises Izuku is making, he seems to be succeeding.

"Is this what you thought about?" asks Katsuki.

Izuku tightens his legs around him on a hard thrust. "Ah! Th-thought about?"

"When you were touching yourself," says Katsuki, "just on the other side of this wall."

"Y-yeah," admits Izuku breathlessly. "I... wanted to... f-feel you in me."

Katsuki grins. "I wanted to feel you around me," he says, lowering his hands to Izuku's hips and starting to ram into him harder. Izuku's cries grow louder, especially when Katsuki lowers one hand down between them to start stroking Izuku's cock.

"Katsuki!" Izuku whimpers. "I'm... oh my god, I'm getting close."

"I am too," groans Katsuki. "You feel amazing Izuku."

Anything more Izuku might be about to say is swallowed by a higher cry as he comes hard, white spurting over their stomachs. The feeling of Izuku clenching around him draws another moan from Katsuki and he soon comes too, keeping up his movements to make sure they ride out the pleasure together. When Izuku eventually sags in his arms, Katsuki pulls him close again and carries him back to the bed to sink down onto it with him, kissing him deeply.

"You're amazing," Izuku sighs as they break apart again.

Katsuki runs slow fingers over Izuku's skin, enjoying the feeling of him being so close. "So are you."

"So... would you want to do this again sometime?" Izuku asks.

Katsuki grins. "I think so."


End file.
